Timing values

Timing values

Timing values

The following diagram illustrates the timing increments for rendering a
page:

Figure 1. Client Transaction Timing

The variables in this diagram are defined as follows:

Table 1. Timing Values

Variable

Description

start_time

The date and time the user requests a page (the user clicks on a link). This
value is set by hooking into the beforeunload event of the
previous page. The beforeunload event is not properly supported
by WebKit browsers, which is why the client timings are not supported on Safari or
Chrome.

load_time

The date and time that the current page starts loading in the browser. This
value is set by an inline javascript that runs as the first script in the HTML
body.

server_time

The time in ms spent by the server processing the transaction. The server
reports this value to the client.

load_completion_time

The date and time that the page is fully rendered in the browser. This
operation is performed as the last script on the page and identifies the time the
page completed loading.

The following times are reported by the client in the
syslog_client_transaction table:

Table 2. Timing Values

Label

Element

Description

Calculation

Response Time

client_response_time

Calculates the overall time to deliver the page by subtracting the time the
user requests the page from the time the page is fully rendered in the
browser.

load_completion_time - start_time

Server Time

client_server_time

This is the time the server takes to process the transaction.

server_time

Network Time

client_network_time

Calculates the time the network takes to process the request by subtracting
the time of the user's request from the time the page starts loading in the
browser, and then subtracting the server processing time.

load_time - start_time - server_time

Browser Time

browser_time

Calculates the time the browser takes to deliver the page by subtracting the
time the page is fully rendered from the time the page starts loading in the
browser.